In many applications, a non-metallic material is used in place of metal to reduce the weight or cost of a component or for providing different properties. These non-metallic materials may be ceramics or composites, such as graphite epoxy. When composites or ceramics are used, problems are introduced which relate to the joining of the non-metallic component to other materials. One particular example of this type of problem relates to the inclusion of a metallic bearing component within a composite or ceramic structure. Another example relates to the fastening of two composite or ceramic structures, such as mating housing components, to each other. A further example is a carbon/graphite seal in a surrounding metal housing.
Present methods of joining a composite or ceramic component have relied on some form of mechanical means, such as fasteners, bolts or rivets, to provide a mechanical bond. However, these types of bonds tend to be weaker than the parent materials and, therefore, are prone to premature fatigue-type failure due to their flexing and delaminating nature.
Some attempts at solving these problems have involved methods of ion-beam implantation. Ion-beam-induced atomic mixing is a well known technique for improving the bonding at an interface between dissimilar materials. It has been widely known that bombarding the interface between two materials with low energy ions in the nuclear stopping region causes the two media to intermix and results in the creation of a molecular bond which is much stronger than the traditional mechanical bond. Such a method of ion-beam implantation is exemplified in U.S. Pat No. 4,457,972 issued July 3, 1984 to Griffith et al, and U.S. Pat. No. 4,526,624 issued July 2, 1985 to Tombrello et al. Both patents disclose a method for improving the adhesion between a metal film and a substrate material wherein the materials are first brought into contact and then high energy ions are applied to the interface between the two surfaces. Such a method has the disadvantage that the two materials must first be brought into contact before the high energy ions may be applied.
There is a need for an improved ion-beam implantation method wherein the high energy ions are applied to the surface of the substrate material for joining with a bondable material or a second substrate material.